What is the maximum storage time or shelf life of C8051Fxxx and other IC devices in their original packaging?
While an absolute maximum shelf life for C8051Fxxx, EFM8, and other IC devices may not be explicitly specified, there are requirements for shelf life and device handling that are based on JEDEC standards and device moisture sensitivity level (MSL). The MSL and E-Time are listed on the package anti-moisture/anti-static bag, as shown in the following knowledge base article:
Generally speaking, Silicon Labs packaging and handling procedures conform to JEDEC standard J-STD-033C, which defines Handling, Packing, Shipping and Use of Moisture/Reflow Sensitive Surface Mount Devices standards. According to this document, devices properly packed and sealed have a shelf life of 12 months from the date of seal, and if the storage time is between 12 months and 2 years, the devices can still be mounted on a PCB and soldered if the humidity indicator card (HIC) contained withing the sealed package indicates that baking is not necessary. If either the shelf storage time exceeds 2 years or the HIC indicates a humidity level that requires re-baking, then the devices must be re-baked to remove excess moisture prior to mounting and soldering. The required baking times and procedures are described in the JEDEC standard J-STD-033C (https://www.jedec.org/document_search?search_api_views_fulltext=j-std-033c).
After devices in a sealed package have been opened (i.e. the anti-moisture bag has been opened), they are subject to a floor life, which is dependent on the moisture sensitivity level (MSL) of the device. For instance, in the case of the C8051F340-GQ, the MSL is 3, which corresponds to a floor life of 168 hours in an environment of <=30 deg C and 60% relative humidity. Note that this time is subject to change under different ambient temperature and humidity conditions. After the floor time has been exceeded, device baking is required to ensure safe moisture levels. The MSL for Silicon Labs devices can be found on the packaging (i.e. anti-moisture/anti-static bag label) or through the Environmental and Quality Database, as described in the following knowledge base article: